Merge from origin/emacs-24
[emacs.git] / lisp / vc / ediff-merg.el
blob72dfc0861f5b306478f074b84a03e45c8d2fb2ee
1 ;;; ediff-merg.el --- merging utilities
3 ;; Copyright (C) 1994-2015 Free Software Foundation, Inc.
5 ;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
6 ;; Package: ediff
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software: you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation, either version 3 of the License, or
13 ;; (at your option) any later version.
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
23 ;;; Commentary:
25 ;;; Code:
28 ;; compiler pacifier
29 (defvar ediff-window-A)
30 (defvar ediff-window-B)
31 (defvar ediff-window-C)
32 (defvar ediff-merge-window-share)
33 (defvar ediff-window-config-saved)
35 (require 'ediff-init)
36 (require 'ediff-util)
38 (defcustom ediff-quit-merge-hook 'ediff-maybe-save-and-delete-merge
39 "Hooks to run before quitting a merge job.
40 The most common use is to save and delete the merge buffer."
41 :type 'hook
42 :group 'ediff-merge)
45 (defcustom ediff-default-variant 'combined
46 "The variant to be used as a default for buffer C in merging.
47 Valid values are the symbols `default-A', `default-B', and `combined'."
48 :type '(radio (const default-A) (const default-B) (const combined))
49 :group 'ediff-merge)
51 (defcustom ediff-combination-pattern
52 '("<<<<<<< variant A" A ">>>>>>> variant B" B "####### Ancestor" Ancestor "======= end")
53 "Pattern to be used for combining difference regions in buffers A and B.
54 The value must be a list of the form
55 \(STRING1 bufspec1 STRING2 bufspec2 STRING3 bufspec3 STRING4)
56 where bufspec is the symbol A, B, or Ancestor. For instance, if the value is
57 '(STRING1 A STRING2 Ancestor STRING3 B STRING4) then the
58 combined text will look like this:
60 STRING1
61 diff region from variant A
62 STRING2
63 diff region from the ancestor
64 STRING3
65 diff region from variant B
66 STRING4
68 :type '(choice (list string symbol string symbol string)
69 (list string symbol string symbol string symbol string))
70 :group 'ediff-merge)
72 (defcustom ediff-show-clashes-only nil
73 "If t, show only those diff regions where both buffers disagree with the ancestor.
74 This means that regions that have status prefer-A or prefer-B will be
75 skipped over. A value of nil means show all regions."
76 :type 'boolean
77 :group 'ediff-merge
79 (make-variable-buffer-local 'ediff-show-clashes-only)
81 (defcustom ediff-skip-merge-regions-that-differ-from-default nil
82 "If t, show only the regions that have not been changed by the user.
83 A region is considered to have been changed if it is different from the current
84 default (`default-A', `default-B', `combined') and it hasn't been marked as
85 `prefer-A' or `prefer-B'.
86 A region is considered to have been changed also when it is marked as
87 as `prefer-A', but is different from the corresponding difference region in
88 Buffer A or if it is marked as `prefer-B' and is different from the region in
89 Buffer B."
90 :type 'boolean
91 :group 'ediff-merge
93 (make-variable-buffer-local 'ediff-skip-merge-regions-that-differ-from-default)
95 (defvar state-of-merge) ; dynamic var
97 ;; check if there is no clash between the ancestor and one of the variants.
98 ;; if it is not a merge job then return true
99 (defun ediff-merge-region-is-non-clash (n)
100 (if (ediff-merge-job)
101 (string-match "prefer" (or (ediff-get-state-of-merge n) ""))
104 ;; If ediff-show-clashes-only, check if there is no clash between the ancestor
105 ;; and one of the variants.
106 (defun ediff-merge-region-is-non-clash-to-skip (n)
107 (and (ediff-merge-job)
108 ediff-show-clashes-only
109 (ediff-merge-region-is-non-clash n)))
111 ;; If ediff-skip-changed-regions, check if the merge region differs from
112 ;; the current default. If a region is different from the default, it means
113 ;; that the user has made determination as to how to merge for this particular
114 ;; region.
115 (defun ediff-skip-merge-region-if-changed-from-default-p (n)
116 (and (ediff-merge-job)
117 ediff-skip-merge-regions-that-differ-from-default
118 (ediff-merge-changed-from-default-p n 'prefers-too)))
121 (defun ediff-get-combined-region (n)
122 (let ((pattern-list ediff-combination-pattern)
123 (combo-region "")
124 (err-msg
125 "ediff-combination-pattern: Invalid format. Please consult the documentation")
126 region-delim region-spec)
128 (if (< (length pattern-list) 5)
129 (error err-msg))
131 (while (> (length pattern-list) 2)
132 (setq region-delim (nth 0 pattern-list)
133 region-spec (nth 1 pattern-list))
134 (or (and (stringp region-delim) (memq region-spec '(A B Ancestor)))
135 (error err-msg))
137 (condition-case nil
138 (setq combo-region
139 (concat combo-region
140 region-delim "\n"
141 (ediff-get-region-contents
142 n region-spec ediff-control-buffer)))
143 (error ""))
144 (setq pattern-list (cdr (cdr pattern-list)))
147 (setq region-delim (nth 0 pattern-list))
148 (or (stringp region-delim)
149 (error err-msg))
150 (setq combo-region (concat combo-region region-delim "\n"))
153 ;;(defsubst ediff-make-combined-diff (regA regB)
154 ;; (concat (nth 0 ediff-combination-pattern) "\n"
155 ;; regA
156 ;; (nth 1 ediff-combination-pattern) "\n"
157 ;; regB
158 ;; (nth 2 ediff-combination-pattern) "\n"))
160 (defsubst ediff-set-state-of-all-diffs-in-all-buffers (ctl-buf)
161 (let ((n 0))
162 (while (< n ediff-number-of-differences)
163 (ediff-set-state-of-diff-in-all-buffers n ctl-buf)
164 (setq n (1+ n)))))
166 (defun ediff-set-state-of-diff-in-all-buffers (n ctl-buf)
167 (let ((regA (ediff-get-region-contents n 'A ctl-buf))
168 (regB (ediff-get-region-contents n 'B ctl-buf))
169 (regC (ediff-get-region-contents n 'C ctl-buf)))
170 (cond ((and (string= regA regB) (string= regA regC))
171 (ediff-set-state-of-diff n 'A "=diff(B)")
172 (ediff-set-state-of-diff n 'B "=diff(C)")
173 (ediff-set-state-of-diff n 'C "=diff(A)"))
174 ((string= regA regB)
175 (ediff-set-state-of-diff n 'A "=diff(B)")
176 (ediff-set-state-of-diff n 'B "=diff(A)")
177 (ediff-set-state-of-diff n 'C nil))
178 ((string= regA regC)
179 (ediff-set-state-of-diff n 'A "=diff(C)")
180 (ediff-set-state-of-diff n 'C "=diff(A)")
181 (ediff-set-state-of-diff n 'B nil))
182 ((string= regB regC)
183 (ediff-set-state-of-diff n 'C "=diff(B)")
184 (ediff-set-state-of-diff n 'B "=diff(C)")
185 (ediff-set-state-of-diff n 'A nil))
186 ((string= regC (ediff-get-combined-region n))
187 (ediff-set-state-of-diff n 'A nil)
188 (ediff-set-state-of-diff n 'B nil)
189 (ediff-set-state-of-diff n 'C "=diff(A+B)"))
190 (t (ediff-set-state-of-diff n 'A nil)
191 (ediff-set-state-of-diff n 'B nil)
192 (ediff-set-state-of-diff n 'C nil)))
195 (defun ediff-set-merge-mode ()
196 (normal-mode t)
197 (remove-hook 'local-write-file-hooks 'ediff-set-merge-mode))
200 ;; Go over all diffs starting with DIFF-NUM and copy regions into buffer C
201 ;; according to the state of the difference.
202 ;; Since ediff-copy-diff refuses to copy identical diff regions, there is
203 ;; no need to optimize ediff-do-merge any further.
205 ;; If re-merging, change state of merge in all diffs starting with
206 ;; DIFF-NUM, except those where the state is prefer-* or where it is
207 ;; `default-*' or `combined' but the buf C region appears to be modified
208 ;; since last set by default.
209 (defun ediff-do-merge (diff-num &optional remerging)
210 (if (< diff-num 0) (setq diff-num 0))
211 (let ((n diff-num)
212 ;;(default-state-of-merge (format "%S" ediff-default-variant))
213 do-not-copy state-of-merge)
214 (while (< n ediff-number-of-differences)
215 (setq do-not-copy nil) ; reset after each cycle
216 (if (= (mod n 10) 0)
217 (message "%s buffers A & B into C ... region %d of %d"
218 (if remerging "Re-merging" "Merging")
220 ediff-number-of-differences))
222 (setq state-of-merge (ediff-get-state-of-merge n))
224 (if remerging
225 ;;(let ((reg-A (ediff-get-region-contents n 'A ediff-control-buffer))
226 ;; (reg-B (ediff-get-region-contents n 'B ediff-control-buffer))
227 ;; (reg-C (ediff-get-region-contents n 'C ediff-control-buffer)))
228 (progn
230 ;; if region was edited since it was first set by default
231 (if (or (ediff-merge-changed-from-default-p n)
232 ;; was preferred
233 (string-match "prefer" state-of-merge))
234 ;; then ignore
235 (setq do-not-copy t))
237 ;; change state of merge for this diff, if necessary
238 (if (and (string-match "\\(default\\|combined\\)" state-of-merge)
239 (not do-not-copy))
240 (ediff-set-state-of-merge
241 n (format "%S" ediff-default-variant)))
244 ;; state-of-merge may have changed via ediff-set-state-of-merge, so
245 ;; check it once again
246 (setq state-of-merge (ediff-get-state-of-merge n))
248 (or do-not-copy
249 (if (string= state-of-merge "combined")
250 ;; use n+1 because ediff-combine-diffs works via user numbering
251 ;; of diffs, which is 1+ to what ediff uses internally
252 (ediff-combine-diffs (1+ n) 'batch)
253 (ediff-copy-diff
254 n (if (string-match "-A" state-of-merge) 'A 'B) 'C 'batch)))
255 (setq n (1+ n)))
256 (message "Merging buffers A & B into C ... Done")
260 (defun ediff-re-merge ()
261 "Remerge unmodified diff regions using a new default. Start with the current region."
262 (interactive)
263 (let* ((default-variant-alist
264 (list '("default-A") '("default-B") '("combined")))
265 (actual-alist
266 (delete (list (symbol-name ediff-default-variant))
267 default-variant-alist)))
268 (setq ediff-default-variant
269 (intern
270 (completing-read
271 (format "Current merge default is `%S'. New default: "
272 ediff-default-variant)
273 actual-alist nil 'must-match)))
274 (ediff-do-merge ediff-current-difference 'remerge)
275 (ediff-recenter)
278 (defun ediff-shrink-window-C (arg)
279 "Shrink window C to just one line.
280 With a prefix argument, returns window C to its normal size.
281 Used only for merging jobs."
282 (interactive "P")
283 (if (not ediff-merge-job)
284 (error "ediff-shrink-window-C can be used only for merging jobs"))
285 (cond ((eq arg '-) (setq arg -1))
286 ((not (numberp arg)) (setq arg nil)))
287 (cond ((null arg)
288 (let ((ediff-merge-window-share
289 (if (< (window-height ediff-window-C) 3)
290 ediff-merge-window-share 0)))
291 (setq ediff-window-config-saved "") ; force redisplay
292 (ediff-recenter 'no-rehighlight)))
293 ((and (< arg 0) (> (window-height ediff-window-C) 2))
294 (setq ediff-merge-window-share (* ediff-merge-window-share 0.9))
295 (setq ediff-window-config-saved "") ; force redisplay
296 (ediff-recenter 'no-rehighlight))
297 ((and (> arg 0) (> (window-height ediff-window-A) 2))
298 (setq ediff-merge-window-share (* ediff-merge-window-share 1.1))
299 (setq ediff-window-config-saved "") ; force redisplay
300 (ediff-recenter 'no-rehighlight))))
303 ;; N here is the user's region number. It is 1+ what Ediff uses internally.
304 (defun ediff-combine-diffs (n &optional batch-invocation)
305 "Combine Nth diff regions of buffers A and B and place the combination in C.
306 N is a prefix argument. If nil, combine the current difference regions.
307 Combining is done according to the specifications in variable
308 `ediff-combination-pattern'."
309 (interactive "P")
310 (setq n (if (numberp n) (1- n) ediff-current-difference))
312 (let (reg-combined)
313 ;;(setq regA (ediff-get-region-contents n 'A ediff-control-buffer)
314 ;; regB (ediff-get-region-contents n 'B ediff-control-buffer))
315 ;;(setq reg-combined (ediff-make-combined-diff regA regB))
316 (setq reg-combined (ediff-get-combined-region n))
318 (ediff-copy-diff n nil 'C batch-invocation reg-combined))
319 (or batch-invocation (ediff-jump-to-difference (1+ n))))
322 ;; Checks if the region in buff C looks like a combination of the regions
323 ;; in buffers A and B. Return a list (reg-a-beg reg-a-end reg-b-beg reg-b-end)
324 ;; These refer to where the delimiters for region A, B, Ancestor start and end
325 ;; in buffer C
326 (defun ediff-looks-like-combined-merge (region-num)
327 (if ediff-merge-job
328 (let ((combined (string-match (regexp-quote "(A+B)")
329 (or (ediff-get-state-of-diff region-num 'C)
330 "")))
331 (mrgreg-beg (ediff-get-diff-posn 'C 'beg region-num))
332 (mrgreg-end (ediff-get-diff-posn 'C 'end region-num))
333 (pattern-list ediff-combination-pattern)
334 delim reg-beg reg-end delim-regs-list)
336 (if combined
337 (ediff-with-current-buffer ediff-buffer-C
338 (while pattern-list
339 (goto-char mrgreg-beg)
340 (setq delim (nth 0 pattern-list))
341 (search-forward delim mrgreg-end 'noerror)
342 (setq reg-beg (match-beginning 0))
343 (setq reg-end (match-end 0))
344 (if (and reg-beg reg-end)
345 (setq delim-regs-list
346 ;; in reverse
347 (cons reg-end (cons reg-beg delim-regs-list))))
348 (if (> (length pattern-list) 1)
349 (setq pattern-list (cdr (cdr pattern-list)))
350 (setq pattern-list nil))
353 (reverse delim-regs-list)
356 ;; Check if the non-preferred merge has been modified since originally set.
357 ;; This affects only the regions that are marked as default-A/B or combined.
358 ;; If PREFERS-TOO is non-nil, then look at the regions marked as prefers-A/B as
359 ;; well.
360 (defun ediff-merge-changed-from-default-p (diff-num &optional prefers-too)
361 (let ((reg-A (ediff-get-region-contents diff-num 'A ediff-control-buffer))
362 (reg-B (ediff-get-region-contents diff-num 'B ediff-control-buffer))
363 (reg-C (ediff-get-region-contents diff-num 'C ediff-control-buffer)))
365 (setq state-of-merge (ediff-get-state-of-merge diff-num))
367 ;; if region was edited since it was first set by default
368 (or (and (string= state-of-merge "default-A")
369 (not (string= reg-A reg-C)))
370 (and (string= state-of-merge "default-B")
371 (not (string= reg-B reg-C)))
372 (and (string= state-of-merge "combined")
373 ;;(not (string= (ediff-make-combined-diff reg-A reg-B) reg-C)))
374 (not (string= (ediff-get-combined-region diff-num) reg-C)))
375 (and prefers-too
376 (string= state-of-merge "prefer-A")
377 (not (string= reg-A reg-C)))
378 (and prefers-too
379 (string= state-of-merge "prefer-B")
380 (not (string= reg-B reg-C)))
384 (provide 'ediff-merg)
387 ;; Local Variables:
388 ;; eval: (put 'ediff-defvar-local 'lisp-indent-hook 'defun)
389 ;; eval: (put 'ediff-with-current-buffer 'lisp-indent-hook 1)
390 ;; eval: (put 'ediff-with-current-buffer 'edebug-form-spec '(form body))
391 ;; End:
393 ;;; ediff-merg.el ends here